ALLIANT ENERGY CORP

Ticker: LNT CUSIP: 018802108 Class: COM

WILLIAM BLAIR INVESTMENT MANAGEMENT, LLC's Holding History (CIK: 0001644956)

Note: Option positions (PUT/CALL) are excluded.

Q1 2019

Shares 19,476 Value ($000) $918 Avg Close $36.14 Range $32.70 - $38.77

Q4 2018

Shares 21,607 Value ($000) $913 Avg Close $35.19 Range $32.65 - $37.38

Q3 2018

Shares 23,463 Value ($000) $999 Avg Close $34.13 Range $32.72 - $35.18

Q2 2018

Shares 22,000 Value ($000) $931 Avg Close $32.46 Range $30.20 - $34.35

Period	Shares	Value ($000)	Average Close	Price Range
Q1 2019	19,476	$918	$36.14	$32.70 - $38.77
Q4 2018	21,607	$913	$35.19	$32.65 - $37.38
Q3 2018	23,463	$999	$34.13	$32.72 - $35.18
Q2 2018	22,000	$931	$32.46	$30.20 - $34.35